Submersible Bilge Pump for 1-2ms PPM Signal @ 50Hz

[Martin2013]

Hi,

Would anyone know where I can find a submersible bilge pump that understands a 1-2ms ppm signal at 50Hz?
I would like to control a bilge pump using the HobbyKing KK2.0 Flight control board ( http://www.hobbyking.com/hobbyking/store/__31656__Hobbyking_KK2_0_Multi_rotor_LCD_Flight_Control_Board_UK_Warehouse_.html ).

I have been desperately trying to find one!

Thank you!



Martin2013

 

[billblack]

Just so we are clear -I believe you mean a PWM signal.
I have wired a number of bilge pumps and am not aware of an RC control capable bilge pump or one that is meant to operate at anything less than 100% of capacity. They are merely intended to be made inexpensively and run reliably.
The only way that I am aware of to convert an RC signal to motor control PWM is to put a motor controller between your flight control board and the pump. Something like this:( http://www.pololu.com/product/1373 ) would work, I believe. The larger pumps can pull a considerable amount of power, so be sure to test the pump's power usage fully loaded before you size your motor control board. The 2100 GPH bilge pump in the stern of my boat will draw 10+ amps with a full head of water.
Hope that helps.

 

[Martin2013]

Just so we are clear -I believe you mean a PWM signal.
I have wired a number of bilge pumps and am not aware of an RC control capable bilge pump or one that is meant to operate at anything less than 100% of capacity. They are merely intended to be made inexpensively and run reliably.
The only way that I am aware of to convert an RC signal to motor control PWM is to put a motor controller between your flight control board and the pump. Something like this:( http://www.pololu.com/product/1373 ) would work, I believe. The larger pumps can pull a considerable amount of power, so be sure to test the pump's power usage fully loaded before you size your motor control board. The 2100 GPH bilge pump in the stern of my boat will draw 10+ amps with a full head of water.
Hope that helps.

Thanks a lot for your reply.
So you suggest I link the KK2.0 board to the motor controller and link the motor controller to the speed controller? All of this for the 4 motors?
Which bilge pump do you suggest I use?
Thanks a lot for your help!

 

[pbuk]

Why on Earth would you want a variable speed control on a bilge pump? Just wire it through a float valve switch - if there is water in the bilge it gets pumped out, if there isn't it doesn't.

 

[Martin2013]

Why on Earth would you want a variable speed control on a bilge pump? Just wire it through a float valve switch - if there is water in the bilge it gets pumped out, if there isn't it doesn't.

That's because I'm building an underwater quadcopter.

 

[billblack]

I thought that might be your intent. An underwater ROV in quadcopter form...ought to be a masters thesis in hydrodynamics.
and yes, you will have to feed the motor controllers a signal they can understand, so be sure to get controllers that will take a PWM signal. In addition the controllers will have to support reversing the motor(s). Many do not.
Any of the cartridge style bilge pumps that you see available in stores have replacement motor cartridges. 360 gmh and 500 gph pumps are usually used, depending in the size of the vehicle. A model boat prop fits right on the output shaft. Google "DIY ROV" and you will find several descriptions of bilge pumps used as ROV thrusters.
The very best book on underwater vehicle design, construction and control is at the following link. It costs about $100 US and will be the cheapest thing you buy considering the time and money it will save you.
http://www.marinetech.org/underwater-robotics-textbook/